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The threatened South‐eastern Long‐eared Bat (Nyctophilus corbeni, EPBC Act 1999 Vulnerable) is an insectivorous microbat that is dependent on tree hollows for roosting. Although it is sparsely distributed throughout the Murray‐Darling Basin, its contemporary Victorian distribution was believed to be limited to a small population in semi‐arid mallee habitats in the state's North‐West. That was until a lactating female was captured in the floodplain forest in Gunbower National Park, along the Murray River in north‐central Victoria, in late 2021. In light of this new record, in an ecological setting not typically occupied by the species, we sought to (a) confirm the presence of an established population of N. corbeni at Gunbower; and (b) if present, characterize the day roosts being used. Over eight nights (73 trapnights), we captured 172 microbats, including five N. corbeni. Traps set with acoustic lures (the Autobat MK2, or a generic bat chirper) appeared to capture more bats per trapnight than those set without lures. Four individual N. corbeni were successfully radiotracked to their roosts, which were a mix of small‐diameter (19.5–36 cm DBH), typically multi‐stemmed, live, dying and dead Black Box (Eucalyptus largiflorens) and Grey Box (Eucalyptus microcarpa) trees. While day roosts do not appear to be limiting for this species in this location, further research is needed to understand what trees are being used as maternity roosts (which may be more specialized), how far up‐ and down‐stream along the Murray River this new population extends, and whether it is geographically and/or genetically connected to populations in the Victorian mallee or in New South Wales. [ABSTRACT FROM AUTHOR]

Within its core highland range, Leadbeater's possum (Gymnobelideus leadbeateri) occurs predominantly in tall montane ash forest dominated by Eucalyptus regnans, E. delegatensis and E. nitens. To improve predictive modelling of suitable habitat, we surveyed ash/non-ash ecotones and also explored the species' recently extended eastern distribution. We detected Leadbeater's possums at 19 sites, including six in non-ash forest dominated by £ dalrympleana, E. viminalis or E. kybeanensis. This extends its known distribution by 5.5 km and appears to delineate the north-eastern limit of its range. Our results add to previous findings indicating Leadbeater's possums have slightly broader range limits and habitat flexibility than previously thought. [ABSTRACT FROM AUTHOR]

Summary: Every macropod population is unique in terms of the combination of species, site and management goals, so there is no universal 'best' method for surveying populations. We distinguish between different measures of abundance and the confidence a manager can place in them. We examine the separate components of survey methods: the survey platform, mode of detection and form of sampling. We also review the range of current methods available and highlight new developments, including their assumptions and limitations. To guide managers in choosing a method for their management context, we provide a decision matrix based on the behavioural ecology of the target species, the structure of habitat at the site and the porosity of the site boundary. To promote current best practice, we describe in detail four standard counting methods: direct count, sweep count, faecal accumulation rate and distance sampling. [ABSTRACT FROM AUTHOR]

• Arboreal camera trapping used to assess post-fire occurrence of Leadbeater's possum. • Unburnt refugia in local landscape positively influences post-fire occupancy. • Sites with higher pre-fire disturbance had higher Leadbeater's possum occupancy. • Proximity to unburnt habitat outside the fire perimeter did not influence occupancy. • Population recovery likely driven by in situ survival rather than recolonisation. Large wildfires have the potential to create heterogeneous landscapes in forest ecosystems. Range-restricted species in fire-prone regions have evolved to persist in the face of periodic disturbance due to wildfire. However, the factors that enable them to do so are often poorly understood. Whether post-fire population recovery is driven by survival of individuals within the burnt area (in situ recovery) or by recolonisation from unburnt habitat outside the fire perimeter (ex situ recovery), and over what timeframe this occurs, is valuable knowledge for conservation management. Understanding post-fire population dynamics is important when considering whether management interventions are required to prevent local extinctions. We examined the influence of fire-derived landscape context on site occupancy by the critically endangered Leadbeater's possum Gymnobelideus leadbeateri in south-eastern Australia, 6–11 years after a large wildfire in 2009. Our aim was to assess whether site occupancy was influenced by fire extent in the local landscape, distance from unburnt habitat outside the fire perimeter, and/or pre-fire disturbance history. We used arboreal camera trapping to survey Leadbeater's possums within the burnt area, using 732 cameras at 245 sites. We used occupancy modelling to estimate the effects on site occupancy of (1) unburnt habitat surrounding sites (500 m radius), (2) distance from unburnt habitat at the fire perimeter, and (3) whether the site had been disturbed by either fire or timber harvesting in the decades prior to the 2009 fire. Leadbeater's possums were detected at 78 of the 245 sites (32 %). Site occupancy was positively influenced by the presence of unburnt habitat within 500 m, and was higher at sites that had experienced disturbance between the 2009 fire and the previous major wildfire in 1939. Proximity to unburnt habitat outside the fire perimeter did not influence occupancy. Our results suggest that population recovery was driven primarily by in situ survival and recovery, rather than via recolonisation from source populations outside the burnt area. Our findings indicate that Leadbeater's possum populations are more likely to recover from fires that are more heterogeneous in their severity, leaving relatively more unburnt patches within their perimeter. Post-fire management interventions such as translocation to facilitate population recovery are likely unnecessary for this species, provided surviving individuals have spatial continuity of habitat to enable recolonisation. Management strategies aimed at the retention of unburnt patches within the footprint of future fires will likely promote the post-fire recovery of arboreal mammal species in fire-prone forests, particularly under a changing climate with increased frequency and intensity of wildfires. [ABSTRACT FROM AUTHOR]

Reference intervals (RIs) describe baseline parameters of healthy animals, providing a powerful tool for wildlife managers to monitor health, identify disease and assess animal welfare. This paper reports haematological, glucose and serum protein RIs for one of Australia's most iconic and managed mammals, the eastern grey kangaroo Macropus giganteus. Blood samples (n = 514) were collected from 11 populations of eastern grey kangaroos, across much of their geographic range. A species-level RI was initially established based on samples collected from four sites (n = 245) and was further partitioned based on significant differences associated with sexual maturity and season. Unique population means were established from a further seven sites to investigate the importance of biotic (sex and sexual maturity) and abiotic (season, site, rainfall, temperature and laboratory) factors on kangaroo health parameters. Random forest analysis of health parameters revealed that abiotic factors (site, rainfall, temperature and season) were largely responsible for differences in haematological, glucose and serum protein values. Sex was found to have no influence, while sexual maturity and laboratory of analysis had moderate effects. Based on these findings, interpretation of individual and population haematological and serum protein values requires careful consideration of the timing of sample collection, environmental conditions and sexual maturity. When assessing kangaroo health, the relevant sexual maturity RI must be considered initially. For populations with similarities to those described (for example high density or captive populations) users should also consider site specific mean haematological and serum protein values. The RIs reported are valuable when establishing the health status of kangaroo populations. Furthermore, understanding the influence of biotic and abiotic factors will improve the utility of these RIs to assess health, disease status and improve welfare in eastern grey kangaroos. [ABSTRACT FROM AUTHOR]

The transmission of pathogens between wildlife and livestock is a globally recognised threat to the livestock industry, as well as to human and wildlife health. Wild cervids are susceptible to many diseases affecting livestock. This presents a challenge for wildlife and domestic animal disease management because the frequent use of agricultural areas by wild cervids may hamper the effectiveness of disease control strategies.Six deer species have established wild populations in Australia and are expanding in range and abundance. A comprehensive literature review of diseases impacting deer and livestock was undertaken, resulting in consideration of 38 pathogens. A qualitative risk assessment was then carried out to assess the overall risk posed by the pathogens to the livestock industry.Five diseases (bovine tuberculosis, foot and mouth disease, malignant catarrhal fever, surra, and screw‐worm fly infestation) ranked highly in our risk assessment. Of these five diseases, only one (malignant catarrhal fever) is currently present in Australia, but all five are notifiable diseases at a national level. Data on these diseases in deer are limited, especially for one of the most abundant species, the sambar deer Rusa unicolor, highlighting a further potential risk attributable to a lack of understanding of disease epidemiology.This paper provides a detailed review of the pathogens affecting both cervids and livestock in Australia, and applies a qualitative framework for assessing the risk posed by deer to the livestock industry. The qualitative framework used here could easily be adapted to assess disease risk in other contexts, making this work relevant to scientists and wildlife managers, as well as to livestock industry workers, worldwide. [ABSTRACT FROM AUTHOR]

Most urban mammals are small. However, one of the largest marsupials, the Eastern Grey Kangaroo Macropus giganteus, occurs in some urban areas. In 2007, we embarked on a longitudinal study of this species in the seaside town of Anglesea in southern Victoria, Australia. We have captured and tagged 360 individuals to date, fitting each adult with a collar displaying its name. We have monitored survival, reproduction and movements by resighting, recapture and radio-tracking, augmented by citizen science reports of collared individuals. Kangaroos occurred throughout the town, but the golf course formed the nucleus of this urban population. The course supported a high density of kangaroos (2-5/ha), and approximately half of them were tagged. Total counts of kangaroos on the golf course were highest in summer, at the peak of the mating season, and lowest in winter, when many males but not females left the course. Almost all tagged adult females were sedentary, using only part of the golf course and adjacent native vegetation and residential blocks. In contrast, during the non-mating season (autumn and winter), many tagged adult males ranged widely across the town in a mix of native vegetation remnants, recreation reserves, vacant blocks, commercial properties and residential gardens. Annual fecundity of tagged females was generally high (≥70%), but survival of tagged juveniles was low (54%). We could not determine the cause of death of most juveniles. Vehicles were the major (47%) cause of mortality of tagged adults. Road-kills were concentrated (74%) in autumn and winter, and were heavily male biased: half of all tagged males died on roads compared with only 20% of tagged females. We predict that this novel and potent mortality factor will have profound, long-term impacts on the demography and behavior of the urban kangaroo population at Anglesea. [ABSTRACT FROM AUTHOR]

Lactation is the most energetically expensive component of reproduction in mammals. Theory predicts that reproducing females will adjust their behaviour to compensate for increased nutritional demands. However, experimental tests are required, since comparisons of the behaviour of naturally reproducing and non-reproducing females cannot distinguish between true costs of reproduction, individual differences or seasonal variation. We experimentally manipulated reproduction in free-ranging, eastern grey kangaroos (Macropus giganteus), using a fertility control agent. Our novel field experiment revealed that females altered their behaviour in direct response to the energetic demands of reproduction: reproducing females increased bite rates, and thus food intake, when the energetic demands of lactation were highest. Reproducing females did not reduce the time spent on vigilance for predators, but increased their forage intake on faecal-contaminated pasture, thereby increasing the risk of infection by gastrointestinal parasites-a largely unrecognized potential cost of reproduction. [ABSTRACT FROM AUTHOR]

Mammalian herbivores are typically infected by parasitic nematodes, which are acquired through direct, faecal-oral transmission. These parasites can cause significant production losses in domestic livestock, but much less is known about impacts on wild mammalian hosts. We review three elements of parasitism from the host's perspective: fitness costs of infection, risks of infection during foraging and benefits of nutritious pasture. The majority of wildlife studies have been observational, but experimental manipulation is increasing. Treatment with anthelmintics to manipulate parasite load has revealed varied impacts of parasites on fitness variables across host species, but has not produced consistent evidence for parasite-induced anorexia or impaired body condition. Some experimental studies of infection risk have manipulated faecal contamination and detected faecal avoidance by hosts. Only two field studies have explored the trade-off between infection risk and nutritional benefit generated by avoidance of contaminated patches. Overall, field studies of costs, risks and benefits of the host-parasite relationship are limited and few have examined more than one of these elements. Parasitism has much in common with predation, and future insights into anti-parasite responses by wild hosts could be gained from the conceptual and technical developments in research on anti-predator behaviour.This article is part of the Theo Murphy meeting issue 'Evolution of pathogen and parasite avoidance behaviours'., (© 2018 The Author(s).)